ĐÁNH GIÁ ĐỘ TIN CẬY VÀ ỨNG DỤNG CỦA BỘ CÂU HỎI IPAQ-SF TRONG ĐO LƯỜNG HOẠT ĐỘNG THỂ LỰC Ở NGƯỜI CAO TUỔI CÓ THOÁI HÓA KHỚP GỐI

Abstract

Backgrounds: Knee osteoarthritis is a common musculoskeletal disorder in adults and older people, characterized by chronic pain, limited range of motion, and functional impairment. The prevalence of the disease increases with age and is often associated with risk factors such as overweight, obesity, and a sedentary lifestyle, thereby significantly affecting daily activities and quality of life.

In clinical practice, assessment of physical activity plays an important role in monitoring and managing patients. The IPAQ–SF questionnaire is widely used due to its simplicity and ability to estimate energy expenditure; however, in Vietnam, there is still a lack of studies evaluating its reliability among older adults with knee osteoarthritis. Therefore, this study was conducted to assess the reliability of the IPAQ–SF in this population, providing scientific evidence for its application in practice and research.

Objectives: This study aimed to determine the reliability of the IPAQ–SF questionnaire among community-dwelling older adults with knee osteoarthritis in 2025 by assessing its stability and internal consistency. Specifically, the study used the intraclass correlation coefficient (ICC) to evaluate test–retest reliability and Cronbach’s alpha to assess internal consistency, as well as describing the duration and energy expenditure of physical activity based on the IPAQ–SF.

Methods: The study was conducted on 110 older adults with knee osteoarthritis (12 males and 98 females), all meeting the diagnostic criteria of NICE. According to these criteria, knee osteoarthritis is identified when patients present with activity-related joint pain, no or minimal morning stiffness lasting no more than 30 minutes, and mechanical knee pain. After screening, all participants were assessed using the International Physical Activity Questionnaire – Short Form (IPAQ–SF), and the collected data were used for statistical analyses in the study.

Results: The study participants were mainly in the 60–69 (48,2%) and 70–79 (45,8%) age groups, with BMI mostly classified as overweight (55,5%) and normal (40,9%), while underweight and obesity were both 1.8%. Regarding IPAQ–SF, mean weekly durations were 63,9 ± 222,1 min for VPA (median 0), 636,0 ± 431,0 min for MPA (median 630), 198,3 ± 199,4 min for walking (median 140), and 163,2 ± 81,7 min/day for sitting; corresponding frequencies were 0,9 ± 2,2; 6,2 ± 2,1, and 4,9 ± 3,0 days/week, respectively. Energy expenditure was 511,6, 3816,0, and 654,5 MET-min/week for VPA, MPA, and walking. Reliability analysis showed excellent ICC for VPA (0,98), MPA (0,98), and sitting time (0,96), and good reliability for walking (0,77) - all p < 0,001; while Cronbach’s alpha was 0,688 - indicating acceptable internal consistency.

Conclusions: The IPAQ–SF demonstrated good reliability in older adults with knee osteoarthritis and acceptable internal consistency. In addition, this tool effectively captured physical activity levels, describing both activity duration and energy expenditure. Overall, the IPAQ–SF is an appropriate instrument for assessing physical activity in this population.